Electric switch



Dec. 15, 1942. H. L. VAN VALKENBURG ETAL 2,304,972

ELECTRIC SWITCH Filed Nov. 24, 1939 2 s t s t 2 4 9 4 7 1 2 a a 1 f M H1 1 M 7 w T M A J A w n/WM m 7% 5 $7 1 H M WNV v A n j f m M v k g 5.liqfi. a d3 U 4 5.4, Q 1 mj 7 w a 4 6 m Patented Dec. 15, 19422,304,972 ELECTRIC swrrcn- Hermon L. Van Valkenburg, Josef Bierenfeld,Milwaukee,

Wauwatosa, and Wis., assignors to Square D Company, Detroit, Mich., acorporation of Michigan Application November 24, 1939, Serial No.305,880

' 9 Claims. (01. 200-165) This invention relates to electromagneticallyoperated electric switches and has for its general object the provisionof an electric switch of sturdy and economical construction withimproved operating characteristics and provision for easy accessibilityand ready convertibility of its Operating parts.

Another object of this present invention is the provision of an electricswitch in which the cooperating contacts may be readily changed fromnormally open to normally closed, and vice versa, in the field andwithout the addition of any parts.

Another object of the present invention is the provision of an electricswitch having an improved means of mounting the movable contacts intheir normally closed position.

Other objects and features of this invention will be readily apparent tothose skilled in the art from the specification and appended drawingsillustrating certain preferred embodiments in which:

Figure 1 is a front elevational view of an electromagnetic switchaccording to the present invention.

Figure 2 is a sectional view on the line 11-11 of Figure 1.

Figure 3 is a sectional view on the line IIIIII of Figure 1 enlarged andshowing the construction of the mounting means.

Figure 4 is a view similar to Figure 2 but with the contacts in theclosed position.

Figure 5 is a bottom plan view of the electromagnetic switch of thepresent invention.

Figure 6 is a sectional view taken on line VL-VI of Figure 1.

Figure 7 is a view showing the contacts in normally closed position.

The electric switch, according to the present invention, comprises arear supporting plate i upon which is mounted, by means of studs 5, a

contact block 2 having a plurality of individual switching recesses3formed therein by plurality ofspaced barrier walls 4. Withineach recess3, at the front and rear thereof, are mounted stationary contactassemblies 6 and 1. The contact assemblies 6, mounted at the front ineach chamber 3, are identical to one another, and the contact assembliesI, mounted at the rear, are also identical. Each stationary contactassembly 6 comprises an L-shaped contact element 8 having a contact face9 secured to the outside of a leg II. The contact element 3 in turn issecured as by a stud l2 to a C-shaped conductor i3 supported at thefront of block 2 in a manner to be hereinafter described. The contactelement 8 is cut away as at I4 to engage with a teat l5 provided uponthe conductor i3 for properly positioning the element 8. Carried uponthe upper portion of the conductor I3 and at right angles to one anotherare terminal clamps l6 and their cooperating terminal screws IT. Theconductor element i3 is held in position upon the block 2 by means of ahorizontal leg i8 at the bottom which bears against the contact block,and a return bent portion at the top secured by stud i9 to an upstandingledge 2| on the block.

Disposed at the rear of a recess 3 is the stationary contact assembly 1comprising an 'L- shaped contact element 23 having a contact face 24secured upon the inner face of its leg 25.- It

' is to be noted that the contact face 22 is disposed upon a differentface of its supporting leg than is the contact face 9 upon thecorresponding leg ii. The contact element 23 is secured as by a stud 26to a conductor element 21 which extends through an opening in the roofof the block 2 to the exterior thereof and is secured to the block by astud 28. This conductor element carries at its outer extremity aterminal clamp 29 similar to the terminal clamp IS. A teat 3| isprovided upon the lower extremity of the conductor 21 to cooperate witha cutaway portion on contact element 23 to position it. An insulatingsheet 32 is disposed between the rear face of block 2 and the supportingplate I.

The movable contact assembly comprises an insulating supporting block 33having mounted thereon a plurality of generally U-shaped supports 34which have their free ends bent inwardly as at 35 to maintain a contactplate 36 within the legs of the UV-shaped supports. Within each of theU-shaped supports 34 is disposed a compression spring 3! adapted to biasthe movable contact plate 36 against the bent portion 35. Th spring 31is maintained in place by spaced spring seats provided by a pressedoutportion 38 on contact plate 36 and the extremity of a stud 39 whichsecures the U-shaped support 34 to the contact block 33. Upon themovable contact plate 36 and at the ends thereof are disposed contactsurfaces-4i and 42 adapted to cooperate with the stationary contactfaces 9 and 24. The thickness of contact plate 36 is less than thedistance between the bent portions 35 so that the contact plate may beeasily inserted edgewise and then upon being turned flat will be pressedagainst these bent portions by biasing spring 31. The insulating contactblock 33 is secured to a movable generally U-shaped supporting member 43and is movable thereby to carry the movable contacts into engagementwith the stationary contacts. The stationary magnet structure 49 is madeup of generally E-shaped magnetic laminations and a pair of supportingbrackets 44 riveted together into a rigid structure. The brackets havefront flanges 48 for the reception of other parts and rear flanges 44which are secured to plate I by studs 45 to support the magnet structurein place. Pressed out portions 41 are provided on the plate I to assistin properly positioning the bracket flanges. Disposed about the centralleg of the magnet 49 are two U-shaped guide pieces 5| over which isfitted an operating coil 52 having terminals 51. The coil 52 ismaintained in place upon this central leg by means of the L-shapedstraps 53 having leg portions engageable with the bottom face of thecoil. A stud 54 secures both the u-shaped guide pieces 5| and a pair ofL-shaped straps 53 to the magnet 49. A shading coil 56 is placed uponeach of the other legs-f the E-shaped magnet 49. Cooperating with themagnet 49 is a T-shaped armature 58 having its leg 59 disposed withinthe opening between the opposed U- shaped guide pieces and movabletherein upon energization of the coil 52. The lower leg port-lons of theU-shaped supporting member 43 are provided with openings therethroughadapted to receive a removable pin 62. A pair of swinging resilient arms53 are mounted on opposite sides of the supporting member 43 and serveto maintain the pin 62 in place. Pivotally supported upon pin 52 is thearmature 58, the pin passing through an opening in the head portionthereof. Spacers 54 are carried by the supporting member 43 and serve toproperly position the armature 58 upon pin 52. Thus, when armature 53moves vertically upon energization of coil 52, the supporting member 43will move in the same direction through its connection by pin 62 to saidarmature 58.

In front of the supporting member 43 and rigidly secured to the brackets44 by studs 55 threaded into the bent portions 48 of the brackets is aguide member 55. A vertical leg 51 spaced backwardly by the horizontalleg 53 of the guide member is received within a slot 59 extending intothe base of the contact block 33 to guide the contact block in itsreciprocatory movement. iVhile the guide member 58 is in place thesupporting member 43 though reciprocably movable cannot be removed fromthe switch. A flat hinge plate 1|, having a pair of eared portions 12and 13 at each end, interconnects the lower ends of guide member 66 andsupporting member 43. The ears 12 are received in slots provided in theguide member 68 and the ears 13 are received in slots provided in aflange 16 on the supp rting member 43. A spring 11 interconnects theguide member 56 and the flange and exerts its bias upon said members soas to hold the eared portions 12 and I3 of the plate ll within theirrespective slots. The provision of the pivotal construction serves toproperly position the moving parts of the switch with respect to theircooperating parts and to provide for substantially rectilinear movementof the armature and movable contacts. This arrangement also permits thearmature and movable contacts to be readily removed from and assembledon the switch. The spring ll further provides a biasing force whichassists the force of gravity in returning the switch parts to "oilposiil m.

The operation and function of the parts will now be described:

The switch, as shown in Figures 1 and 2, is in the off position. Uponenergization of coil 52, the armature 58 will be attracted to the E-shaped stationary magnet 49 and through the pin 62 will move thesupporting mamber 43 vertically, stretching the spring 19 and carryingthe insulating supporting block 33 secured to said member 43 in a likdirection to move the contact surfaces 4| and 42 into engagement withthe stationary contacts 9 and 24 and complete the circuit'through theswitch. Upon the deenergization of the coil 52, the armature 58 willmove away from the stationary contact structure under the force ofgravity assisted by the spring Il, thus moving the block 33 andassociated movable contacts downwardly to separate the movable contactsfrom the stationary contacts. The contacts are guided in theirreciprocatory movement into and out of engagement by the cooperation offlange 51 of the guide member 65 with slot 69 in the base of the contactcarrying block 33.

The contact arrangement above described is adapted for the readyconversion of the cooperating stationary and movable contacts intoeither the normally closed or normally open type. In the device shown inFigure 2, the contacts have been illustrated as of the normally opentype. To change to a normally closed type, illustrated in Figure 7, itis only necessary to turn the contact plate 38 on edge and slip it outfrom between the legs of the U-shaped support 34 through the spaceprovided between the bent portions remove the contact elements 8 and 23,place the contact plate 38 within the upper portion of contact chamber33 with its contact surfaces 4| and 42 facing downwardly and with thebiasing spring 31 disposed within a recess 19 provided in the roof ofblock 2 to exert its bias against the back of the contact plate 36 thenremount the contact elements 8 and 23 upon the block 2 but interchangetheir positions upon th block so that the element 23 will be secured toconducting element I3 at the front of the contact chamber and theelement 3 will be secured to the conducting element 21 disposed in therear of the contact chamber. This reversal of position will cause thecontact surfaces 3 and 24 carried by said elements to now be facingupwardly instead of downwardly and the movable contacts 4| and 42 willbe placed into engagement therewith under the bias of spring 31 tothereby furnish a normally closed switch. It is to be noted that therehas been no addition or elements, merely a simple interchange of parts.With the arrangement 01 parts, energization of coil 52 will cause thesupports 34 to engage contact plates 38 and move them upwardly todisengage the contacts.

To mount the supporting plate I upon a panel or other surface foroperation, there is provided a novel mounting means shown in detail inFigure 3, and comprising a mounting screw 3| having threads upon itsextremity, a sleeve 82 having a headed portion 33 and a longitudinalbore 34 therethrough with th extremity of said bore opposit-e said headbeing threaded, and a rubber grommet 85 fitting over the sleeve 32 andhaving a peripheral slot receiving the edges 01' an opening in the plateI. To mount the plate I, the grommet 35 is fitted into the opening inplate I, the sleeve 82 inserted therethrough so that the head 83 bearsupon the rear portion of the grommet, and the mounting screw 8| threadedthrough the sleeve and into a threaded opening in the surface to whichit is to be attached. Washers 88 are disposed upon the screw 8| betweenthe head of the screw and the end of the sleeve 82. By thisconstruction, an entirely resilient mounting forthe switch supportingplate is provided which will minimize both transmission and reception ofvibration from the switch operating parts.

While certain pr ferred embodiments of this invention have beenspecifically disclosed, it is understood that the invention is notlimited thereto, as many variations will be readily apparent to thoseskilled in the art and the invention is to be given its broadestpossible interpretation within the terms of the following claims:

What is claimed is:

1. In an electric switch, an insulating structure, a pair of spacedstationary contacts mounted on said structure, a movable contact adaptedto cooperate with said stationary contacts to bridge the same, means foreffecting movem nt of said movable contact into and out of engagementwith the stationary contacts, said stationary contacts being ofdissimilar form and non-interchangeable with their contact surfacesfacing in the same direction, but readily interchangeable when I saidcontact faces are reversed, and said stationary contacts beingnon-reversible with respect to contact facing without said interchange,said movable contact being inversely mountable to cooperate with saidstationary contacts in either position to provide a normally open or anormally closed switch optionally without additional parts.

2. In an electric switch, an insulating block having a plurality ofcontact recesses therein, a plurality of stationary contacts disposedwithin said chambers at the front and'rear thereof, a plurality ofbridging movable contacts adapted to cooperate with said stationarycontacts, Operating means for moving the movable contacts, said frontand rear stationary contacts being of dissimilar form andnon-interchangeable with their contact surfaces facing in the samedirection but readily interchangeable when the facing of their contactsurfaces is reversed and non-reversible without interchange, saidcontact surfaces cooperating with normally open movable contacts whenfacing in one direction and when interchanged and reversed cooperatingwith normally closed movable contacts.

3. In an lectric switch, an insulating block, a

plurality of stationary contacts mounted adjacent to the front thereof,a plurality of stationary contacts mounted adjacent to the rear thereof,a plurality of movable contacts adapted to bridge the aligned front andrear stationary contacts, operating means for moving the movable con- 4tacts, said front stationary contacts being noninterchangeable with saidrear stationary contacts except when the direction in which the contactsurfaces face is reversed and said contacts being non-reversible withrespect to the facing of their contact surfaces except upon interchangeof the front and rear stationary contacts, and said movable contactsbeingreadily reversably mountable for cooperation with saidinterchangeable stationary contacts in both positions to provide anormally open or a normally closed switch without additional parts.

4. In an electric switch, an insulating block having a plurality. ofcontact recesses therein, a pair of horizontally spaced stationarycontacts disposed within each of said recesses, movable contacts adaptedto bridge said stationary contacts, supporting means for said movablecontacts movable in said recesses to move said movable contacts,operating means having an operative connection with said movable contactsup- 76 porting meansto provide for movement of the movable contacts toperform the switching p ation, said horizontally spaced contacts beingof dissimilar form and non-interchangeable with their contact surfacesfacing in the same direction but readily interchangeable when the facingof the contact surfaces is reversed and being nonreversible with respectto contact surface facing without interchange, and said movable contactsbeing inversely mountable so as to cooperate with said interchangeablestationary contacts in each of their positionsto provide a switch ofthenormally open or normally closed type without additional parts. 7 a

5. In an electric switch, an insulating block having a plurality ,ofcontactchambers therein, a plurality of stationary contacts disposed threin at the front and rear thereof, a plurality of terminal meansconnected to said stationary contacts, movable contacts adapted .tobridge said stationary contacts, a member movable for moving saidmovable contacts, said front and rear stationary contacts being ofdissimilar form and non-interchangeable except upon reversal of thedirection of their contact surfaces facing and their contact surfacesbeing non-reversible without interchange of the front and rear contacts,said movable contacts being inversely mountable to cooperate with saidinterchangeable stationary contacts in each of their positions toprovide a switch of the normally open or normally closed type.

6. In a switch, an insulating structure, a pair of horizontally spacedstationary contacts mounted on said structure, terminal meanscooperating with each of said spaced stationary contacts, movablecontacts adapted to bridge said spaced stationary contacts, a movableoperator, said movable contacts being optionally mountable either uponsaid insulating structure, facing downwardly or upon said movableoperator facing upwardly, operating means for said movable operator,said horizontally spaced stationary contacts being readilyinterchangeable with one another to cooperate with said movable contactin both positions to provide a switch of the normally open or normallyclosed type.

7. In a switch, an insulating block having a one operating positionwithin said recesses in normally closed relation, said movable contactsbeing mountable upon said operating means in their second operatingposition and cooperating with said stationary contacts when interchangedin normally open relation.

8. In an electric switch, an insulating block having a, pluralityofcontact chambers therein, terminals means mounted at the front andrear of said insulating block and extending within said contactchambers, oppositely extending contact carrying elements secured to saidterminal means, movable contacts adapted to bridge the contacts carriedby said elements, the front and rear elements being readilyinterchangeable and adapted in one position to support the movablecontacts within the contact chambers to provide 9. normally closedcircuit control, resilient means biasing said movable contacts againstthe contacts on said elements when in said one position, means movableto move said movable contacts to disengaged position, said means beingadapted to support said movable contacts in a second position forcooperation with the contact carrying elements when interchanged toprovide a normally open circuit control, and operating means for e1-fecting movement of said movable member.

9. In an electric switch, an insulating block having a plurality ofcontact chambers therein, terminal means mounted at the front and rearof said insulating block and extending within said chambers, oppositelyextending contact carrying elements secured to said terminal means andwith the contact surfaces thereon disposed upwardiy, movable contactsbridging said contact surfaces and supported within said contact chamherby said contact carrying elements to thereby provide normally closedcircuit control, means movable to move said movable contacts todisengaged position, said contact carrying elements being readilyinterchangeable with each other to cause the contact surfaces thereon toface downwardly, the movable contacts being adapted to be supported bysaid movable means and to be moved thereby into engagement with saidcontact surfaces, when facing downwardly to provide normally opencircuit control, and operating means for effecting movement of saidmovable member to perform the switching operation.

HERMON L. VAN VALKENBURG.

JOSEF BIERENFELD.

